Mozambique  Porifera, sponges
The identifications were only made on the basis of the photographs which is very hazardous for most of the species. As a consequence the Latin names might not be accurate.
The books used for the identification are listed: bibliography.

Following Lecointre, what we call "sponges", poriferans is not an homogeneous group, it's paraphyletic: the group contains its most recent common ancestor, but does not contain all the descendants of that ancestor... If you consider a familly, it's like having the parents, three children, their descendants but not the fourth one and its offspring.
So, we've got three groups : Demosponges, Hexactinellida and Calcarea. 90% of sponges are demosponges and its the only group illustrated here.
To get a basic knowledge on this group I would suggest Wikipedia.
Exhaustive data base on sponges: World Porifera database